The new mural of the artist group Die Schlumper is just outside their atelier. I could find out at least one of the artists: Horst Wässle.

"The Schlumpers are an artists’ group founded in 1980 by the Hamburg artist Rolf Laute (1940–2013). The origin of the Schlumper group came from an idea Rolf Laute had for a wall painting in the Wilfried Borck House at the Alsterdorf institute for the handicapped to be created with the participation of some of the house’s artistically talented residents. Today, this group of artists, with differing handicaps and individual artistic attitudes, is celebrated internationally. Self-determination and free artistic activity are the group’s basic principles. The German name “Die Schlumper” comes from the name of the Hamburg street “Beim Schlump” where the artists’ first studio was located." Source: https://www.schlumper.de/en/who-are-the-schlumper/The